I was reading Orthodox Chinese Buddhism of Master Sheng Yen. In page 185 he said something, well, it sound funny for me :lol

"Note that the four heavens of the realm of formlessness are not
physical locations, and so cannot be shown on the chart. According to
scroll 3? of the Complete Chronicle of the Buddha and Patriarchs,
there exist countless billion-world universes. The billion-world universe we
live in is called the Universe of Tribulation, which is said to be theshape of “space.”Other billion-world universes are said to be shaped
like a turtle shell, a swastika, a half-moon, a square, an octagon, a tower,
and other shapes."

I want to know, where does he take this in bold? What could be his source for this?

I mean, I haven't read anything like that in sutras, perhaps is some kind of Chinese folklore?

"Note that the four heavens of the realm of formlessness are not
physical locations, and so cannot be shown on the chart. According to
scroll 3? of the Complete Chronicle of the Buddha and Patriarchs,
there exist countless billion-world universes. The billion-world universe we
live in is called the Universe of Tribulation, which is said to be theshape of “space.”Other billion-world universes are said to be shaped
like a turtle shell, a swastika, a half-moon, a square, an octagon, a tower,
and other shapes."

I want to know, where does he take this in bold? What could be his source for this?

I mean, I haven't read anything like that in sutras, perhaps is some kind of Chinese folklore?

The turtle is mentioned in various Tao stories. The shell was a symbol of heaven, and the underside was a symbol of earth. Maybe, in the context above, it had a more recondite meaning which would have been understood by Taoists at that time,

Universe in the form of a wheel is mentioned in Sutra and Abhidharma, I have seen it in many books, one of them is Early Buddhist Theory of Knowledge by K. N. Jayatilleke.
I am sure that at least some of these other forms of a universe are mentioned in the Flower Ornament Scripture/ Avatamsaka Sutra.

svaha"All human beings are born free and equal in dignity and rights.
They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood."
(Universal Declaration of Human Rights, Article 1.)

Flower Ornament Scripture: Formation of Worlds, p. 189:
"Children of Buddha, the oceans of worlds have various different forms and characteristics. That is to say, some are round, some square, some neither round nor square. There are infinite distinctions. Some are shaped like whirlpools, some like mountains of flames, some like trees, some like flowers, some like palaces, some like living creatures, some like Buddhas. There are as many forms such as these as there are atoms in an ocean of worlds."

In the verse section: "Some are round, some are square,
Some triangular, some octagonal;
Gemstone-wheel shaped, lotus blossoms, and so on:
All are different, according to deeds."

svaha"All human beings are born free and equal in dignity and rights.
They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood."
(Universal Declaration of Human Rights, Article 1.)

Sorry! The Jayatilleke source is wrong, I was remembering an essay of Jaytilleke named The Buddhist Conception of the Universe. This essay is currently available in The Message of the Buddha by K. N. Jayatilleke, a posthumous collection of essays and writings of Jayatilleke.

svaha"All human beings are born free and equal in dignity and rights.
They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood."
(Universal Declaration of Human Rights, Article 1.)

svaha"All human beings are born free and equal in dignity and rights.
They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood."
(Universal Declaration of Human Rights, Article 1.)